BaTiO_(3)纳米线的长径比对聚间苯二甲酰间苯二胺复合材料介电性能的影响

Influence of BaTiO_(3) Nanowire Aspect Ratio on Dielectric Property of Poly(Metaphenylene Isophthalamide) Composite

用水热法合成了不同长径比的钛酸钡纳米线(BaTiO_(3)nanowires (BTN)),用聚乙烯吡咯烷酮(PVP)调节其表面化学能和静电力(标记为P-BTN)。将P-BTN加入聚间苯二甲酰间苯二胺(PMIA)基体中制备出P-BTN含量(质量分数)为10%的介电复合材料P-BTN/PMIA。研究了合成温度对BTN长径比的影响、P-BTN对P-BTN/PMIA复合材料介电性能和电学性能的影响以及P-BTN/PMIA复合材料在不同温度下的介电性能和电学性能。结果表明:随着BTN合成温度的提高其长径比明显增大,从130℃时的7.2增大到250℃时的46;随着PMIA复合材料中P-BTN长径比的增大其介电常数从6.6增大到9.8,其介电损耗在整个频率范围内小于0.025并保持了良好的绝缘性能;在-20℃-200℃复合材料P-BTN-250-10介电常数和介电损耗保持稳定。高长径比的BTN更利于提高耐高温聚合物基复合材料的介电常数,进而提高其储能密度。

The BaTiO_(3) nanowires(BTN) with different aspect ratios were synthesized through hydrothermal method, and polyvinylpyrrolidone(PVP) was used to adjust the surface chemical energy and electrostatic force of BTN(named as P-BTN). Subsequently, P-BTN were added into poly(metaphenylene isophthalamide)(PMIA) matrix to prepare PMIA dielectric composites containing 10% P-BTN(mass fraction) with different aspect ratios. The influence of synthesized temperature on aspect ratio of BTN was investigated, and the effect of P-BTN with different aspect ratios on dielectric and electrical properties of PMIA composites as well as dielectric and electrical properties of P-BTN/PMIA composites at different temperatures were also investigated. The results show that with increase of synthetic temperature of BTN precursor, the aspect ratios of synthesized BTN significantly increased from 7.2(130℃) to 46(250℃).With increment of the aspect ratio of P-BTN in PMIA composites the dielectric constants of corresponding composites increased from 6.6 to 9.8. At the same time, the dielectric losses of all composites were less than 0.025 in entire frequency range. Furthermore, the prepared composites with different aspect ratios of P-BTN also maintained satisfied insulation performance. The dielectric constant and dielectric loss in the range of-20℃ to 200℃ of P-BTN-250-10 composite maintains stable. This P-BTN/PMIA composites can further increase the energy storage density.